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	<h1 translate="no">PMREMGenerator</h1>
		<section>
			<header>
				<div class="class-description"><p>This class generates a Prefiltered, Mipmapped Radiance Environment Map
(PMREM) from a cubeMap environment texture. This allows different levels of
blur to be quickly accessed based on material roughness. It is packed into a
special CubeUV format that allows us to perform custom interpolation so that
we can support nonlinear formats such as RGBE. Unlike a traditional mipmap
chain, it only goes down to the LOD_MIN level (above), and then creates extra
even more filtered 'mips' at the same LOD_MIN resolution, associated with
higher roughness levels. In this way we maintain resolution to smoothly
interpolate diffuse lighting while limiting sampling computation.</p>
<p>The prefiltering uses GGX VNDF (Visible Normal Distribution Function)
importance sampling based on &quot;Sampling the GGX Distribution of Visible Normals&quot;
(Heitz, 2018) to generate environment maps that accurately match the GGX BRDF
used in material rendering for physically-based image-based lighting.</p></div>
			</header>
			<article>
				<div class="container-overview">
					<h2>Constructor</h2>
					<h3 class="name name-method" id="PMREMGenerator" translate="no">new <a href="#PMREMGenerator">PMREMGenerator</a><span class="signature">( renderer : <span class="param-type"><a href="WebGLRenderer.html">WebGLRenderer</a></span> )</span> </h3>
					<div class="method">
						<div class="description">
							<p>Constructs a new PMREM generator.</p>
						</div>
						<table class="params">
							<tbody>
								<tr>
									<td class="name">
										<strong>renderer</strong>
									</td>
									<td class="description last">
										<p>The renderer.</p>
									</td>
								</tr>
							</tbody>
						</table>
					</div>
				</div>
				<h2 class="subsection-title">Methods</h2>
					<h3 class="name name-method" id="compileCubemapShader" translate="no">.<a href="#compileCubemapShader">compileCubemapShader</a><span class="signature">()</span> </h3>
					<div class="method">
						<div class="description">
							<p>Pre-compiles the cubemap shader. You can get faster start-up by invoking this method during
your texture's network fetch for increased concurrency.</p>
						</div>
					</div>
					<h3 class="name name-method" id="compileEquirectangularShader" translate="no">.<a href="#compileEquirectangularShader">compileEquirectangularShader</a><span class="signature">()</span> </h3>
					<div class="method">
						<div class="description">
							<p>Pre-compiles the equirectangular shader. You can get faster start-up by invoking this method during
your texture's network fetch for increased concurrency.</p>
						</div>
					</div>
					<h3 class="name name-method" id="dispose" translate="no">.<a href="#dispose">dispose</a><span class="signature">()</span> </h3>
					<div class="method">
						<div class="description">
							<p>Disposes of the PMREMGenerator's internal memory. Note that PMREMGenerator is a static class,
so you should not need more than one PMREMGenerator object. If you do, calling dispose() on
one of them will cause any others to also become unusable.</p>
						</div>
					</div>
					<h3 class="name name-method" id="fromCubemap" translate="no">.<a href="#fromCubemap">fromCubemap</a><span class="signature">( cubemap : <span class="param-type"><a href="Texture.html">Texture</a></span>, renderTarget : <span class="param-type"><a href="WebGLRenderTarget.html">WebGLRenderTarget</a></span> )</span><span class="type-signature"> : <a href="WebGLRenderTarget.html">WebGLRenderTarget</a></span> </h3>
					<div class="method">
						<div class="description">
							<p>Generates a PMREM from an cubemap texture, which can be either LDR
or HDR. The ideal input cube size is 256 x 256,
as this matches best with the 256 x 256 cubemap output.</p>
						</div>
						<table class="params">
							<tbody>
								<tr>
									<td class="name">
										<strong>cubemap</strong>
									</td>
									<td class="description last">
										<p>The cubemap texture to be converted.</p>
									</td>
								</tr>
								<tr>
									<td class="name">
										<strong>renderTarget</strong>
									</td>
									<td class="description last">
										<p>The render target to use.</p>
										<p>Default is <code>null</code>.</p>
									</td>
								</tr>
							</tbody>
						</table>
						<dl class="details">
							<dt class="tag-returns"><strong>Returns:</strong> The resulting PMREM.</dt>
						</dl>
					</div>
					<h3 class="name name-method" id="fromEquirectangular" translate="no">.<a href="#fromEquirectangular">fromEquirectangular</a><span class="signature">( equirectangular : <span class="param-type"><a href="Texture.html">Texture</a></span>, renderTarget : <span class="param-type"><a href="WebGLRenderTarget.html">WebGLRenderTarget</a></span> )</span><span class="type-signature"> : <a href="WebGLRenderTarget.html">WebGLRenderTarget</a></span> </h3>
					<div class="method">
						<div class="description">
							<p>Generates a PMREM from an equirectangular texture, which can be either LDR
or HDR. The ideal input image size is 1k (1024 x 512),
as this matches best with the 256 x 256 cubemap output.</p>
						</div>
						<table class="params">
							<tbody>
								<tr>
									<td class="name">
										<strong>equirectangular</strong>
									</td>
									<td class="description last">
										<p>The equirectangular texture to be converted.</p>
									</td>
								</tr>
								<tr>
									<td class="name">
										<strong>renderTarget</strong>
									</td>
									<td class="description last">
										<p>The render target to use.</p>
										<p>Default is <code>null</code>.</p>
									</td>
								</tr>
							</tbody>
						</table>
						<dl class="details">
							<dt class="tag-returns"><strong>Returns:</strong> The resulting PMREM.</dt>
						</dl>
					</div>
					<h3 class="name name-method" id="fromScene" translate="no">.<a href="#fromScene">fromScene</a><span class="signature">( scene : <span class="param-type"><a href="Scene.html">Scene</a></span>, sigma : <span class="param-type">number</span>, near : <span class="param-type">number</span>, far : <span class="param-type">number</span>, options : <span class="param-type">Object</span> )</span><span class="type-signature"> : <a href="WebGLRenderTarget.html">WebGLRenderTarget</a></span> </h3>
					<div class="method">
						<div class="description">
							<p>Generates a PMREM from a supplied Scene, which can be faster than using an
image if networking bandwidth is low. Optional sigma specifies a blur radius
in radians to be applied to the scene before PMREM generation. Optional near
and far planes ensure the scene is rendered in its entirety.</p>
						</div>
						<table class="params">
							<tbody>
								<tr>
									<td class="name">
										<strong>scene</strong>
									</td>
									<td class="description last">
										<p>The scene to be captured.</p>
									</td>
								</tr>
								<tr>
									<td class="name">
										<strong>sigma</strong>
									</td>
									<td class="description last">
										<p>The blur radius in radians.</p>
										<p>Default is <code>0</code>.</p>
									</td>
								</tr>
								<tr>
									<td class="name">
										<strong>near</strong>
									</td>
									<td class="description last">
										<p>The near plane distance.</p>
										<p>Default is <code>0.1</code>.</p>
									</td>
								</tr>
								<tr>
									<td class="name">
										<strong>far</strong>
									</td>
									<td class="description last">
										<p>The far plane distance.</p>
										<p>Default is <code>100</code>.</p>
									</td>
								</tr>
								<tr>
									<td class="name">
										<strong>options</strong>
									</td>
									<td class="description last">
										<p>The configuration options.</p>
										<p>Default is <code>{}</code>.</p>
						<table class="params">
							<tbody>
								<tr>
									<td class="name">
										<strong>size</strong>
									</td>
									<td class="description last">
										<p>The texture size of the PMREM.</p>
										<p>Default is <code>256</code>.</p>
									</td>
								</tr>
								<tr>
									<td class="name">
										<strong>position</strong>
									</td>
									<td class="description last">
										<p>The position of the internal cube camera that renders the scene.</p>
										<p>Default is <code>origin</code>.</p>
									</td>
								</tr>
							</tbody>
						</table>
									</td>
								</tr>
							</tbody>
						</table>
						<dl class="details">
							<dt class="tag-returns"><strong>Returns:</strong> The resulting PMREM.</dt>
						</dl>
					</div>
				<h2 class="subsection-title">Source</h2>
				<p>
					<a href="https://github.com/mrdoob/three.js/blob/master/src/extras/PMREMGenerator.js" translate="no" target="_blank" rel="noopener">src/extras/PMREMGenerator.js</a>
				</p>
			</article>
		</section>
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